Lead time is the end-to-end elapsed time from submitting a purchase order to having sellable inventory available β whether at your warehouse, your 3PL, or Amazon FBA.
Accurate lead time is the foundation of all inventory planning. Underestimate it and you risk stockouts; overestimate it and you accumulate excess inventory and storage fees.
Components of Lead Time
For a typical Amazon FBA product sourced from an overseas manufacturer:
| Stage | Typical Duration |
|---|---|
| Supplier production | 15β45 days (depends on complexity and order size) |
| Quality inspection | 1β3 days |
| Export documentation and freight forwarder handoff | 2β5 days |
| Ocean freight (China to US West Coast) | 20β35 days |
| Customs clearance | 1β5 days |
| Inland trucking to Amazon FC | 2β5 days |
| Amazon FC check-in | 1β7 days |
| Total (sea freight) | 42β100 days |
For air freight, cut transit to 5β7 days but multiply freight cost by 5β10Γ.
Why Lead Time Variability Is the Real Risk
The number to build into your safety stock and reorder point isn't just average lead time β it's maximum lead time. Ocean freight delays (port congestion, weather, Suez/Panama disruptions) regularly add 10β20 days to planned timelines. Q4 factory shutdowns for Chinese New Year push production lead times out by 3β5 weeks starting in January.
Measuring Your Actual Lead Time
Track PO date, goods-ready date, departure date, arrival date, and available-for-sale date for every order. After 5β6 orders, you will have a reliable distribution of actual lead times to use for safety stock calculations rather than relying on supplier estimates.
Reducing Lead Time
- Air freight for small, high-value, or urgent replenishments
- Pre-positioning inventory β send stock to a 3PL near major FCs before it runs out
- Vendor-managed inventory β negotiate with suppliers to hold pre-built safety stock on their side
- Domestic sourcing β for some product categories, US-based suppliers reduce lead time to 2β3 weeks at the cost of higher unit prices